Publications

Quantum tomography protocols with positivity are compressed sensing protocols

Abstract

Characterising complex quantum systems is a vital task in quantum information science. Quantum tomography, the standard tool used for this purpose, uses a well-designed measurement record to reconstruct quantum states and processes. It is, however, notoriously inefficient. Recently, the classical signal reconstruction technique known as ‘compressed sensing’has been ported to quantum information science to overcome this challenge: accurate tomography can be achieved with substantially fewer measurement settings, thereby greatly enhancing the efficiency of quantum tomography. Here we show that compressed sensing tomography of quantum systems is essentially guaranteed by a special property of quantum mechanics itself—that the mathematical objects that describe the system in quantum mechanics are matrices with non-negative eigenvalues. This result has an impact on the way quantum …

Date
December 8, 2015
Authors
Amir Kalev, Robert L Kosut, Ivan H Deutsch
Journal
npj Quantum Information
Volume
1
Issue
1
Pages
1-6
Publisher
Nature Publishing Group